A broad-based coalition of stakeholders has collaborated to reduce excess antibiotic use in Colorado by developing and disseminating clinical practice guidelines and practice profiles to 2600 primary care physicians throughout the state. Whether, how much and what type of public and patient education to employ on large-scale efforts to decrease unnecessary antibiotic use is not known. The Minimizing Antibiotic Resistance in Colorado (MARC) Project is designed to evaluate the independent and combined marginal impact of two common mechanisms of public and patient education in clinician prescribing behavior: 1) household and office-based materials, and 2) mass media (television, radio, newsprint, web site). The following specific aims will examine the processes and outcomes of care related to each intervention strategy. Results from this project will inform state and federal efforts to improve ambulatory antibiotic prescribing practices. Specific Aim IA: Develop and implement community educational interventions using (1) household and office-based materials, and (2) mass media. Specific Aim IB: Measure and assess changes in antibiotic prescription rates for pharyngitis in children, and bronchitis in adults, using commercial MCO and Medicaid administrative data from physician practices. Specific Aim IIA: Conduct household surveys in and outside the intervention communities to measure the impact of each education strategy on public knowledge, attitudes, behavior and self- efficacy. Specific Aim IIB: Conduct a clinician judgment analysis to measure the impact of each education strategy on clinician decision making and empowerment relating to episodes of care for pharyngitis and bronchitis. Specific Aim IIIA: Conduct a survey of patients and parents to measure the impact of decreased antibiotic use on duration of illness and satisfaction with care, for children with pharyngitis and adults with bronchitis. Specific Aim IIIB: Using active surveillance data from the Colorado Department of Public Health and Environment (CDPHE), compare the incidence of invasive penicillin-resistant S. pneumoniae infections in and outside the intervention communities. Specific Aim IIIC: Conduct a net-cost analysis of the different levels of community education.